An Analytical Calculation of Frictional and Bending Moments at the Head-Neck Interface of Hip Joint Implants during Different Physiological Activities
by
Hamidreza Farhoudi 1, Reza H. Oskouei 1,*
, Ali A. Pasha Zanoosi 2, Claire F. Jones 3,4,5 and Mark Taylor 1
Hamidreza Farhoudi 1, Reza H. Oskouei 1,*, Ali A. Pasha Zanoosi 2, Claire F. Jones 3,4,5 and Mark Taylor 1
1
Medical Device Research Institute, Flinders University, Adelaide 5042, Australia
2
Faculty of Industrial & Mechanical Engineering, Qazvin Branch, Islamic Azad University, Qazvin 15195-34199, Iran
3
Adelaide Centre for Spinal Research, Adelaide 5000, Australia
4
School of Mechanical Engineering, University of Adelaide, Adelaide 5005, Australia
5
Centre for Orthopaedic and Trauma Research, School of Medicine, University of Adelaide, Adelaide 5005, Australia
*
Author to whom correspondence should be addressed.
Academic Editor: Saverio Affatato
Materials 2016, 9(12), 982; https://doi.org/10.3390/ma9120982
Received: 10 November 2016 / Revised: 30 November 2016 / Accepted: 1 December 2016 / Published: 5 December 2016
(This article belongs to the Special Issue Corrosion and Tribology of Biomaterials Used in Hip and Knee Arthroplasty)
This study predicts the frictional moments at the head-cup interface and frictional torques and bending moments acting on the head-neck interface of a modular total hip replacement across a range of activities of daily living. The predicted moment and torque profiles are based on the kinematics of four patients and the implant characteristics of a metal-on-metal implant. Depending on the body weight and type of activity, the moments and torques had significant variations in both magnitude and direction over the activity cycles. For the nine investigated activities, the maximum magnitude of the frictional moment ranged from 2.6 to 7.1 Nm. The maximum magnitude of the torque acting on the head-neck interface ranged from 2.3 to 5.7 Nm. The bending moment acting on the head-neck interface varied from 7 to 21.6 Nm. One-leg-standing had the widest range of frictional torque on the head-neck interface (11 Nm) while normal walking had the smallest range (6.1 Nm). The widest range, together with the maximum magnitude of torque, bending moment, and frictional moment, occurred during one-leg-standing of the lightest patient. Most of the simulated activities resulted in frictional torques that were near the previously reported oxide layer depassivation threshold torque. The predicted bending moments were also found at a level believed to contribute to the oxide layer depassivation. The calculated magnitudes and directions of the moments, applied directly to the head-neck taper junction, provide realistic mechanical loading data for in vitro and computational studies on the mechanical behaviour and multi-axial fretting at the head-neck interface.
View Full-Text
▼
Show Figures
Graphical abstract
This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited
MDPI and ACS Style
Farhoudi, H.; Oskouei, R.H.; Pasha Zanoosi, A.A.; Jones, C.F.; Taylor, M. An Analytical Calculation of Frictional and Bending Moments at the Head-Neck Interface of Hip Joint Implants during Different Physiological Activities. Materials 2016, 9, 982.
Show more citation formats
Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.
